The invention relates generally to plant stands for cultivating and growing plants on a vertical structure, and more particularly to a plant stand with an improved watering system for automatically supplying the proper amount of water to each of several regions in the planter.
Various types of upright or vertical planters have been devised to provide indoor and outdoor plant displays which take up relatively little floor space. Vertical or columnar planters have multiple growing locations positioned above one another along a continuous column of soil or other growing medium. One challenge presented by vertical or columnar planters is the even distribution of water for irrigating the plants. In a vertical column of growing medium, water introduced at the top of the column flows downwardly by gravity, tending to over-water lower portions of the column and under-water the top portions.
Several prior art vertical plant growing systems have attempted to deal with the problem of providing even water distribution. For example, U.S. Pat. No. 2,152,869 discloses a vertical planter which consists of multiple separate cells, each of which contains a quantity of growing medium for supporting plant growth in the cell. A water line extends vertically through the planter from cell to cell and each is watered by a separate watering nozzle. The separation between individual cells eliminates downward migration of water to the lower cells, although the planter restricts root growth and plant size for any individual plant to what a single cell can accommodate.
In U.S. Pat. No. 3,063,196, a continuous vertical column of plant-growing medium surrounds a central vertical opening in which a watering tank is positioned. Multiple small openings in the sides of the tank allow water to flow outwardly into the surrounding growing medium. Additional water is supplied to the top of the column of growing medium by providing a small ring-shaped tank above the main tank. The ring-shaped tank is refilled frequently to prevent the top of the column from drying out. The main tank is filled less frequently.
In U.S. Pat. No. 4,268,994, a unitary column of growing medium is watered by a tank positioned above the column using a variety of techniques to attempt to spread the water throughout the medium. In one embodiment, long water-soaked wicks extend from the tank into the medium. In another embodiment, internal walls or baffles retard the downward flow of water through the column.
A problem with prior art approaches to watering plants growing in vertical columns of growing medium is the difficulty of controlling the quantities of water provided at different levels in the column. The above-discussed prior art patents, particularly U.S. Pat. No. 3,063,196, acknowledge the need to provide additional water near the top of the column to prevent drying out. Nevertheless, the system used in U.S. Pat. No. 3,063,196 does nothing to reduce the risk of over-watering the lower part of the planter. The planter is also inconvenient to use, requiring one of its tanks to be refilled frequently.
Still another problem presented by prior art planters, including vertical planters, is that they can be bulky to package and ship and are inconvenient to set up. Planters are generally hollow structures which can waste packaging space and materials. Soil or another growing medium is usually supplied separately from the planter. Before the planter can be used, the soil must be transferred to the hollow interior of the planter.
It would be advantageous to provide a plant growing system which is specifically designed to allow the growing medium to be stored and supplied with the planter, saving space and packaging and simplifying set-up.
It would also be advantageous to have a plant growing system which optimizes the water provided to each plant growing on the planter, without over-watering the lower part of the column of growing medium.
It would also be advantageous to have a watering system for planters which allows selected amounts of water to be distributed to specific regions of the planter.
Accordingly, the present invention provides a plant growing system comprising a container for holding a growing medium in which plants are cultivated. The container has top and bottom ends and side walls extending between the ends to generally surround an interior space. The side walls include a plurality of openings which form plant-growing locations for growing plants in the openings, with the plant roots in growing medium within the container and the foliage of the plants extending along the side walls outside the container. A water distribution system is provided for conducting water to selected regions of the container by means of a plurality of separable branch conduits. One branch conduit, termed the first branch conduit, is formed of one or more tubes supported on the container for supplying water to a first region of the container. A second branch conduit supplies water to a second region of the container, the second region being above the first region. A water supply controller is operatively connected to the water distribution system for supplying selected amounts of water to each branch conduit. In that way, different amounts of water can be supplied to the first and second regions of the container via the respective first and second branch conduits.
The planter structure is suitable for containing, storing and shipping both the planter and the growing medium used to grow plants. During storage and shipment of the planter body, the growing medium is retained within the body by means of a removable enclosure, preferably in the form of flexible sheet material which wraps around the exterior of the body. The removable enclosure closes the openings and retains the growing medium within the body.
In its preferred form, the planter structure is an elongate, cylindrical pipe oriented vertically when in use growing plants. The pipe has an open top and a plurality of openings formed in the cylindrical side walls. Each opening includes a protuberance along the lower edge of the opening forming an outwardly-projecting lip which helps retain the cultivation medium within the opening when the container is in use. A water distribution system on the planter includes a water tank positioned to supply water to the planter by gravity. The tank is preferably positioned on top of the planter. Branch water conduits including one or more water conduit tubes are operatively connected to the tank to conduct water from the tank to selected regions of the container. A plurality of outflow openings positioned at different levels in the tank are connected to the branch conduits. The height of each outflow opening selects the level of water in the tank at which flow into the opening stops as the tank is drained. The outflow openings preferably can be repositioned within the tank. In other words, the height of each outflow opening is adjustable to select the level at which outflow from the tank stops, determining the length of time and quantity of water supplied to each branch conduit during a fill and drain cycle of the tank.